The invention concerns a chain block with a drive motor with a motor shaft, which is connected at the take-off side, across a slip clutch, to a transmission input shaft, having a first gear and mounted in a housing via pivot bearings, of an at least one-stage transmission.
From German patent DE 199 27 847 C1 there is a known chain block with an electric drive motor, whose motor shaft is connected to a secondary transmission. The motor shaft is connected via a slip clutch to an input shaft of the transmission. On the end of the transmission input shaft opposite the drive motor is arranged an electromagnetically activated disk brake. The slip clutch is fashioned as a one or two disk clutch and essentially consists, in the one-disk clutch configuration, of a clutch disk with a clutch lining, joined to the motor shaft so as to rotate with it, and a pressure disk which can be forced against the clutch lining, which is mounted on the transmission input shaft and can move in the lengthwise direction. In order to allow the pressure disk to be subjected to the desired pressing force in the direction of the clutch lining, the pressure disk is connected to a pressure rod, which is led through the transmission input shaft, fashioned as a hollow shaft. The end of the pressure rod projecting out from the end of the transmission input shaft opposite the clutch is connected to a tension spring and a thread adjustment nut so that the pressing force on the pressure rod and thus the maximum torque which can be transmitted by the clutch can be adjusted via the thread adjustment nut. Since the transmission input shaft and the pressure rod project outward beyond the disk brake, the thread adjustment nut is easy to reach for the adjustment. The configuration of the transmission input shaft as a hollow shaft and the use of the pressure rod, on the other hand, are very cumbersome in design.